FIG. 1 is a block diagram of one example of a normal barcode reader. The barcode reader projects light on a barcode, receives reflected light from the barcode and reads the barcode. Specifically, a barcode reading mechanism is as follows. A floodlighting LED 901 projects light on a barcode 903 and concentrates reflected light from the barcode on a CCD (Charge Coupled Device) sensor 907 through a light reception lens 905. Concentrated reflected light is photoelectric-converted with the CCD sensor 907. An amplitude of a reading analog signal, which indicates strength of the reflected light, acquired by the photoelectric-conversion is amplified with an analog amplifier 909, and the amplified analog signal is binarized in a predetermined manner. A digital signal acquired by the binarization is taken in a decoder 911 and decoded by the decoder 911, and thereby data which is encoded in the form of a barcode symbol can be acquired.
Here, the light projected from the floodlighting LED 901 is referred to as scan light. It is referred to as a scan that the scan light is projected on the barcode 903 and the reflected light from the barcode 903 is imaged by an imaging device such as the CCD sensor 907. Here, the scan light may be light which scans the barcode 903 from one end to another end in order according to time or simultaneously.
Meanwhile, in an example illustrated in FIG. 1, a CPU (Central Processing Unit) includes a decoder 911 and a GPIO (General Purpose Input/Output) 913, and the GPIO 913 provides the floodlighting LED 901 with a floodlighting signal. Here, the decoder 911 may be a hardware included in the CPU 915, something like a software which is executed by the CPU 915 reading a program, or a mixture thereof.